Question

【題目】計算下列各題，能簡算的要簡算。0.78×101＝
1.25×0.4×8×2.5＝
64×4.5＋36×4.5＝
13÷0.4÷2.5＝
7.28 ＋3.2÷0.4＝
0.75×18 ÷0.15＝

Answer 1

【答案】78.78；10；450；13；15.28；90
【解析】

0.78×101
=0.78×(100+1)
=0.78×100+0.78×1
=78+0.78
=78.78

1.25×0.4×8×2.5
=(1.25×8)×(0.4×2.5)
=10×1
=10

64×4.5＋36×4.5
=(64+36)×4.5
=100×4.5
=450

13÷0.4÷2.5
=13÷(0.4×2.5)
=13÷1
=13

7.28＋3.2÷0.4
=7.28＋8
=15.28

0.75×18 ÷0.15
=13.5÷0.15
=90
所以答案是：78.78；10；450；13；15.28；90